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General Information





Air Conditioner

Air Conditioner - B1201 Humidity Sensor Short (Low) - General Information

Component Location





General Description

Humidity sensor located at heater control unit detects in-car humidity for in-car humidity control. If ambient air temperature or in-car humidity is outside a specified range, A/C will be activated to control in-car humidity to prevent fogging of the windows.

DTC Description

The ECM sets DTC B1201 if there is a short circuit in humidity sensor signal harness or the measured frequency value of the sensor is less than the threshold value (about 6,186 Hz)

DTC Detecting Condition





Schematic Diagram





Signal Waveform

** Frequency value of humidity sensor as a function of humidity.